Methods
As COVID-19 began to circulate more widely in March and April, 2020, and influenza circulation typically increases during the second half of the calendar year in tropical Asian countries,4 we reviewed WHO influenza surveillance outputs from May 1-December 31, 2020 (epidemiologic weeks 18-53) from tropical Asian countries that have land mass between the Tropics of Cancer and Capricorn.5 We excluded China and Australia, as most areas of those countries have influenza seasons that generally follow temperate rather than tropical seasonal patterns. We then identified countries that tested surveillance specimens for influenza viruses during at least 50% of the 36 weeks (19/36 weeks) between May 1 and December 31, 2020. For each country we report influenza surveillance specimens tested, and the percentage positive for influenza, by type and subtype. We compared current data to historical data from 2015-2019 in order to place the current season in historical context.